I have been looking all over the internet for an example of a sensor that uses the SPI bus on the Pixhawk, and I haven't found anything. It was mentioned in a different discussion that digital airspeed sensors can sometimes work with SPI, but the Pixhawk page for airspeed sensors doesn't mention anything about SPI.
If anyone can give me a link to a sensor that uses the SPI bus, I would really appreciate it. I am hoping to use an I/O expander that uses SPI communication to transmit sensor data to the Pixhawk.
Additionally, it seems like all I2C functional devices just "work" when connected to the flight controller. Mission Planner seems to have an optional hardware tab for most of them. What steps are required in the Ardupilot source code to get all the SPI ports communicating as well?
Thank you for any help.